Automatic crossing block for railways



Feb. 12, 1929.

T. M. CAIN AUTOMATIC CROSSING BLOCK FOR RAILWAYS Filed March 28, 1927 2 Sheets-Sheet. l

INVENTOR 747M? A/ 51/4 ATTORNEY ATTORNEY Patented Feb. 12, 1929.

UNITED STATES PATENT OFFICE.

AUTOMATIC CROSSING BLOCK FOB RAILWAYS.

Application filed March 28, 1927. Serial No. 179,057.

This invention pertains to means for protecting railway crossings from accident, and seeks to provide automatic means for operating safety signals and safety devices for the purposes set forth.

More specifically the invention provides for automatically operated gates to be closed or dropped at the crossing, together with signal bells to be rung at the time the said gates are closed, together with means carried by the gates to render them visible at ni ht.

lhe invention depends upon electrical operationiof various units of the system, the I said electrical operation being set in motion when the train enters the block in question and which is broken when the train leaves the said block. \Vhen the train is oil the block in question the circuit through the various electrical units is broken open, being closed when the train is on the block, the wheels of the train passing over the rails forming the means for closing the said circuit.

The invention is illustrated in the accompanying drawings, in which,

Figure 1 represents a perspective view showing the gates closed and the bells in position,

0 Figure 2 is a wiring diagram illustrating the connections with the various units,

Figure 3 is an elevation of one of the gates showing the arrangement of lights carried to the gates to render the gates visible at night,

Figure 4 is a plan view and operating mechanism,

Figure 5 is an elevation of the gate itself,

Figure 6 is a section on the line 6-6 of Figure tlooking in the direction of the arrows,

Figure 7 is a section taken on 7'(' of Figure 5, and

Figure 8 is a sectional view showing the showing the gate the line automatic switch employed in raising and lowering the gate.

Referring to the drawings it will be seen that the system comprises gates G which may be of the usual drop gate type, or any other form adapting to bar the roadway at the crossing, these gates being intended to be electrically operated by the source of current B, which is any convenient source, or it may be a battery of either the storage or dry battery type, or any other generator of current. Gates G are operated by the moas shown in Figure 4, the operation of the motor resulting in the dropping of the gates G. In order to assure the stoppage of the gate mechanism when the gates have been put in place, there is provided a switch S which adapted to be struck by the gate upon its descent thereby breaking the contact through the motor and stopping the same when the gate is dropped. The switch comprises the contact member S which may be carried upon a metallic leaf or spring carrying a contact 0. When the switch is closed this contact 0 engages the mintact c which is secured to the housing of the switch box (see Figure 8). The construction of this switch such that when the ate is raised-by means of the counter-weight C after the train has passed, the spring of the switch will cause the contacts 0 and n to again engage each other and permit the current to flow for the further actuation of the motor. The contact member S" of the switch is pulled up by the spring member as the gate rises, the switch being closed in operated position. 7

In order to hold the gates in place there is provided a pawl P which is adapted to engage a ratchet R carried by the gate G. This pawl is operated by a solenoid S, the coil of which is magnetized when the circuit is closed thereby causing the pawl to engage the ratchet of the gate and to hold the gate in position. lVhcn the circuit becomes broken the coil S becomes deniagnetized and the spring 8 pulls the pawl back out of contact with the ratchet R of the gate, the gate bein therefore free to spring upward.

W ien the ates are lowered their position will be visibfe by the provision of lights L carried by the gates. Bells B are also connected to the same source of current and further serve as a warning signalling when the gates are closed, which signal will be audible not 0111 when approaching the crossing, but w ion the said crossing is reached. The provision of the bells, while desired, is optional.

The operation of the device is brought about by a train passing into the block in which the present invention is located, this block being shown in Figure 2 b the provision of track insulations I which separate this block from the remainder of the track. The circuit is normally open, but as will be seen from Figure 2 the connection of the circuit together with the connection of the units of the system with the rails are such that as soon as the wheels of the train pass over the track insulation I, the circuit will he closed through the rails and the various units of the system will be operated. The motor M will be set into action which causes the dropping of the gates G, the bells B will be rung, the solenoid magnetized, the motor M deener gized and the gates held into position, as previously described. As soon as the train passes the solenoid circuit is again broken, the gates Gr are raised by their counterweight C, the pawl P having been withdrawn by the operation of the spring a with the demagnetization of the coil 8. It will he apparent from the drawings that the pawl P is pivoted at its lower end to the support so that it is free to move backwards and forwards to secure and release the gates at the proper time.

The gates G are of hollow formation and are provided with window openings 10 upon opposite sides thereof in transverse alinement with the lights L Overlying these openings are transparent panes 11, the latter being held to the gates by clips 12. As

and away from the gate and having ratchet teeth upon one tare r-l :reoi :1 SP1 normally urging the armature away iron! the gate, :1 lug on the gate engagcahlo by the ratchet teeth to retain the gate in horizontal position, and electrical means operable by an approaching train to magnetize the solenoid to engage the ratchet teeth with the lug the sprin functioning to disengage the ratchet teeth IL'OID the lug and permit return of the gate to normal position after the train has passed beyond the gate.

TAYLOR M. CAIN.

horizontal position, 

